For unresectable CRC liver metastases, local ablative therapies are widely applied. Local ablative treatment refers to a variety of intervention techniques that specifically target tumors to directly destroy them. Numerous methods of ablation have been developed including cryoablation, percutaneous ethanol injection, radiofrequency ablation (RFA) and stereotactic radiation therapy. The most widely employed non-radiation based local ablative treatment is RFA which induces thermal ablation by passing high-frequency alternating current through the tumor utilizing electrodes that are placed within the tumor and surrounding tissue. RFA can be applied percutaneously under ultrasonic guidance or directly during laparoscopy or open laparotomy. Local recurrence rates of 44.4% at 18 months were reported by Solbiati et al. for CRC liver metastases with a median diameter of 2.6 cm. For tumors greater than 4 cm the local recurrence rate was 68%. RFA has an overall 3-year survival rate of 28-46% and a 5-year survival rate of 25%. However, patients with advanced hepatic decompensation, large tumors (3 to 5 cm), or multifocal tumors are generally considered poor candidates for RFA.